1. Technical Field
Embodiments of the present disclosure generally relate to semiconductor devices and a semiconductor system relating to an internal temperature and temperature codes.
2. Related Art
In the electronics industry, highly integrated fast volatile memory devices such as high performance dynamic random access memory (DRAM) devices widely used as memory devices are increasingly in demand with the development of high performance electronic systems such as personal computers or communication systems. In particular, when semiconductor devices such as the DRAM devices are employed in cellular phones or notebook computers, the semiconductor devices have to be designed to have an excellent low power consumption characteristic. Accordingly, a lot of effort has been focused on reducing operation currents and standby currents of the semiconductor devices.
A data retention characteristic of a DRAM cell including a single transistor and a single storage capacitor may be very sensitive to temperature. Thus, it may be necessary to control operation conditions of internal circuit blocks in a semiconductor device according to variation of an ambient temperature. For example, DRAM devices employed in mobile systems may be designed to control a refresh period according to variation of an ambient temperature. Temperature sensors such as digital temperature sensor regulators (DTSRs) or analog temperature sensor regulators (ATSRs) have been widely used to control the operation conditions of semiconductor devices such as DRAM devices according to variation of the ambient temperature. These temperature sensors may detect a relatively high temperature and may control an operation period to reduce power consumption in a self-refresh mode. Further, the temperature sensors may monitor an ambient temperature in a normal operation mode.